This Application is the U.S. National Phase Application of PCT International Application No. PCT/GB99/03618 filed Nov. 02, 1999, and published under PCT Article 21(2) in English.
The present invention relates to a rotary deblistering apparatus.
Blister packs for pharmaceutical tablets are generally either xe2x80x9cpush throughxe2x80x9d packs, where manual pushing of the tablet will eject it from the pack through the backing, or xe2x80x9cpeelablexe2x80x9d packs. Peelable packs are intended to be child-resistant, and require the backing to be xe2x80x98peeledxe2x80x99 away before the tablet is accessible. Deblistering of tablets from a push through pack is generally carried out by passing the packs through rollers. Because of the more sealed nature of the peelable pack, deblistering of tablets from such packs is often not possible simply through rollers, and linear or batch processing has been necessary.
According to one aspect of the present invention, there is provided a rotary deblistering apparatus comprising a rotatable drum having a plurality of circumferential pack holding means, each adapted to hold a blister pack, wherein the drum is rotated to locate the pack holding means at a plurality of peripheral work positions including a pack loading position, a pack deblistering position, and a pack detachment position.
The multiplicity of pack holding means on the drum, and the drum""s rotational ability, allow more than one pack to be handled at the same time, increasing the rate of deblistering of the apparatus compared with prior art static deblistering apparatus. Indeed, the present invention is able to provide a continuous operation.
The rotational movement of the drum is preferably indexed, and the drum is preferably stationary at each work position.
The drum may have any number of pack holding means, and be of any suitable size and shape. In one embodiment of the present invention, the drum has the same or similar number of pack holding means as work positions around the drum.
Preferably, the drum is vertically arranged. More preferably, the pack loading position is located wholly or substantially above the drum, to allow gravity to assist loading of a blister pack onto the drum. Similarly, preferably the pack deblistering position and/or the pack detachment position are located wholly or substantially below the drum, to allow gravity to assist the ejection or detachment of the tablets and/or deblistered pack from the drum.
The blister packs can be loaded onto the drum through any suitable loading means. The loading means preferably has a storage magazine able to supply a continuous number of packs to the drum. The loading means could also have a pack selection means to assist individual loading of each pack onto each pack-holding means. The magazine and/or pack selection means is preferably able to deal with curled packs, which are often the most problematic with prior art deblistering apparatus. The pack selection means preferably involves opposing means moveable between pack-edge support and release positions, generally through reciprocal linear and/or rotational motion. Such means include pins, flanges, discs, etc.
A blister pack can be held by a pack holding means using any suitable attachment means, including vacuum, mechanical fastening aids, and/or possibly simple friction fit.
The pack holding means are preferably adapted to match the shape, size and configuration of the design of the pack to be deblistered. The drum also preferably allows each pack holding means to be rapidly and easily changed for different pack designs. The changeability is preferably tool-less, i.e. possible without the need for use of any separate tools such as spanners, keys, screwdrivers, etc.
The deblistering of the tablets from a pack held on the drum can be carried out using suitable mechanical or pneumatic force, eg air, pins, etc. Direct force is generally sufficient for deblistering a push through pack. For a peelable pack, prior weakening or cutting of the backing of the pack may be necessary or desired. Such action could be carried out at the pack deblistering position. Alternatively, there is a prior weakening and/or cutting position around the drum. Such a position could be permanently located, but by-passable or inoperable when the present invention is being used for push through packs.
The pack holding means may be moveable at one or more the work positions to effect the operation on the pack thereat. Alternatively, one or more of the relevant operative means at each work position is moveable when operating on the pack held on the drum.
The present invention may be used for any shape, size and design of blister pack.
According to a second aspect of the present invention, there is provided a method of deblistering one or more blister packs using a rotary deblistering apparatus as herein described, wherein the pack is loaded onto a pack holding means at the pack loading position, rotated to the pack deblistering position where the tablets are forced out of the pack, and the empty pack is then rotated to the pack detachment position where the pack is detached from the pack holding means.
In one embodiment of the method-of the present Invention, the backing of the pack is wholly or substantially cut or weakened at a further work position around the drum.